I am using the LTC4006 Battery Charger to charge a 3-cell battery stack.
My circuit is almost identical to the Circuit Shown on page 20 of the datasheet.
I am also using an LED circuit similar to the one included on the DC495 Demo Board (CHG and C/10 LEDs)
Problem I am having is that when I turn on the charger (DCIN = 15V) with no battery connected, the LEDs switch back and forth every 30-40 seconds, which indicates a change on the CHG pin, which indicates that a charge current is present when there shouldn't be. The output voltage on the BAT pin is a constant 12.6V.
When I turn on the charger with a battery connected, the CHG LED is lit and current flows to the battery as expected. However, when the charge current gets down to around 400mA, it starts fluctuating at about +/- 50mA. Overall it continues to decrease, but the fluctuations do not stop. Also, the CHG LED never turns off, even when the charge current is next to nothing, again indicating that the CHG line is flagging a charge current greater than 200mA.
After a lot of troubleshooting, I can not get the circuit to work as expected. I also cannot get the Demo board to mimic this behavior. Any suggestions are appreciated.
